I have a 1.5kkw 6 panel solar system... 10 years old so it now only pulls about 750w (half). It still works though. I want to get a new 6.6kw system. Does anyone know if the two can run successfully side by side at my house?
Also... while I am at it. Can that happen (or even just the 6.6kw system) on my single phase power connection?
Any ideas or experience out there?
Standard house circuits are protected by an 80 amp pole fuse.
It is generally accepted that 63 amps is the most that a normal single phase house, will use (this is about 15 Kw per hour).
If you have an old system and get a REBATE (say 60cents per kilowatt) if you add to the system or add another system you will loose that rebate.
A 6.6 kw system is limited by the 5kw inverter that is supplied with the system. (The extra 1.6 kw is available on overcast days).
If the additional system is approved by your supplier, then the installer will simply put the new system on the roof, if necessary change your existing PV fuse up to 25 or 32 amps (6.5 kw / 240= 27 amps) and you should be in business.
You need to look at the market when purchasing a new system, look at the inverter supplied, the panels, the warranties etc.
Also if you don't have a smart meter one will be installed (should be free), make sure that the arrangements are made for this.
In SA it is the owner of the new system that has to apply to the supplier for permission to add the system and also to apply to your retailer (AGL) in this case to get the smart meter.
I believe in all other states it is up to either the installer or the selling company to arrange this.
Legally the system is not allowed to be turned on (other than a brief test) unless approved by your supplier.
They hold documents regarding all PV units in your supply area and it is their responsibility to ensure that their maximum capacity (From the GRID or to the GRID is not exceeded).
Hence your request to add new system may be rejected as your local transformer may be close to capacity.
Hope this helps